Automatic wiper for rotary blade



1960 E. R. MILLS AUTOMATIC WIPER FOR ROTARY BLADE Filed Feb. 12, 1959INVENTOR. EMMETT R. MILLS ATTO RN EY United States Patent 2,949,801-AUTOMATIC WIPER FOR ROTARY BLADE Emmett R. Mills, Camas, Wash. FiledFeb. 12, 1959, Ser. No. 792,909 5 Claims. (Cl. 83-168) This inventionrelates to rotary cutters which require frequent grinding or sharpeningwhile in use, and relates in particular to the so-called rotary sawswhich are employed in the paper mills for cutting long rolls of tissueinto the customary toilet roll size.

In order to keep such cutters or roll tissue saws operating at maximumefliciency, and thus enabling them to make quick cuts through the tissuerolls in rapid succession, it is customary to give the cutting edges ofthe blades a momentary sharpening every few minutes. One way in whichsuch sharpening is accomplished without loss of operating time on thepart of the tissue saws is by means of pairs of grinding elements whichare momentarily pressed against the opposite faces of the cutting edgerespectively, such operation of the grinders taking place intermittentlyand preferably automatically. A grinding assembly of this type which hascome into extensive use includes a pair of grinders operatedautomatically at regular intervals every few minutes by compressed airunder electric controls. Oil is applied to both faces of the cutter tofacilitate the cutting action.

A serious problem occasioned by such sharpening of the rotary cutters ortissue saws arises from the fact that with each grinding some grindingparticles and some oil remain on the blades and this residue is thendeposited on the cut edges of the first rolls encountered by the bladesimmediately following their sharpening. This frequently producessufiicient soiling along the cuts to necessitate discarding some of thecut rolls.

An object of the present invention is to provide suitable means forwiping such grinding particles and oil from the cutter blade after eachsharpening operation so as to prevent such residue from being depositedon the rolls which are cut.

A related object of the invention is to provide blade wiping means whichwill wipe both sides of the blade simultaneously.

A further object is to provide such blade wiping means which willoperate entirely automatically and in proper synchronization with theblade sharpening means so as not to cause any operating time to be lostby the blade in the wiping of the blade.

The manner in which these objects are achieved with the blade wiperconstituting the present invention, and the construction and method ofoperation of such blade wiper will be briefly explained and describedwith reference to the accompanying drawings, wherein:

Fig. 1 is a perspective View of the automatic wiper, showing the samemounted in operating position with respect to the rotating blade; and

Fig. 2 is a fragmentary elevation drawn to a larger scale and taken onthe line indicated at 2-2 in Fig. 1, with some portions broken away andparts shown in section for the sake of clarity.

Referring first to Fig. 1, the rotary blade or tissue saw is secured ona shaft 11 which is driven by belt connection 12 with suitable drivingmeans (not shown) causing the blade to rotate rapidly in the clockwisedirection indicated by the arrow x. The blade shaft 11 is rotatablymounted in a support arm 13 which is swung rapidly up and down in an areby suitable means (not shown) so as to cause the blade to be raisedaftereach roll-cutting operation and immediately lowered for the nextroll-cutting operation in the usual manner.

The automatic grinders for the two faces of the rotating blade areomitted from the drawing for clarity, since such grinders are old andwell known and form no part of the present invention. It is to beunderstood, however, that such grinders are operated in the usual mannercompressed air from a suitable source.

The blade wiping assembly is mounted on a plate 14 which is pivotallysupported from a stationary shaft 15, this shaft being parallel to theblade shaft 11. The blade shaft 11 carries a split bearing collar'16with which one end of a rod 17 is connected. The other end of the rod 17is adjustably attached to a bracket 18 on the plate 14, this rod beingattached to the bracket by suitable means such as the clamping bolt andwing nut 19 shown. The plate 14 has a central slot 20 to provide apassageway for the edge of the blade 10. A bumper roll 25 is rotatablymounted on a support bracket 26 near the bottom of the plate 14. Thisbumper roll has a surface of rubber or other soft resilient material andits purpose is to serve as a safety stop for limiting the movement ofthe plate 14 with respect to the blade 10 to prevent any possible damageto the blade, and also to minimize the hazard when any maintenance workis being done on the wiper assembly.

' An electrically-operated,- one-way control valve assembly 21 issupported on the plate 14 and is connected with a suitable source (notshown) of air under pressure by a main air line 22. A branch air line 23connects with the grinders, and the branch air lines 24 and 24' connectwith air cylinders inthe wiper assembly to be described presently.

A pair of supply rolls 27 and 27' of blade-wiping material, such, forexample, as soft paper or tissue, for the blade are rotatably supportedon the plate 14 on opposite sides of the blade respectively and in therelative positions shown in Fig. 1. The supply of tissue 29 from theroll 27 is passed over a pair of guide rolls 30, 30 and drawn between adraw roll 31 and a squeeze roll 33. Similarly the tissue 29' from thesupply roll 27 is passed over the pair of guide rollers 30, 30 and drawnbetween the draw roll 31 and squeeze roll 33, on the opposite side ofthe rotating blade. Spring-pressed friction plates 28 and 28 bearagainst the supply rolls 27 and 27 respectively to prevent the tissuefrom becoming loose on the supply rolls and to prevent inadvertentrotation of the supply rolls. The squeeze rolls 33 and 33', arerotatably mounted on shafts which in turn are supported by means (notshown) causing the squeeze rolls normally to bear against therespective'draw rolls but enabling the squeeze rolls to be moved aslight distance away from the draw rolls when the wiping material isbeing mounted in place.

A pair of air cylinders 34 and 34' are mounted on the plate 14, also onopposite sides of the blade respectively, as shown in Fig. 1. Eachcylinder has a piston, the piston for the cylinder 34 being shown inFig. 2 and designated by the reference character 36. A similar piston iscarried in the cylinder 34 but it is not shown in the drawings. Thepistons in the cylinders 34 and 34' have piston rods 35 and 35'respectively which extend towards the cutter blade and which carrypushers 38 and 38' respectively at their outer ends. These pushers bearagainst the wiping tissue 29 and 29' respectively in the space betweenthe pairs of guide rollers 30, 30 and 30', 30' respectively. Preferablythe pushers 38 and 38 are covered withsoft or resilient material,inasmuch as their lines 24; and-2,4? respectively, with the automaticopera:- assernbly 21, and the delivery.

t on of h valve ontrol of the air-into the cylinders forces the pistons,piston rods and pushersto move towards the respective faces of the bladeand thuscausesv the wiping tissue to be brought into contact with thetwo-faces of the rotating blade. A spring engages the'piston in eachcylinder, the spring 37 in cylinder 34f being shown in Fig. 2. A similarspring bears against the pistonin cylinder 34- but not shown. These;springs cause the pistons, piston rods and pushers to move i -oppositedirection away from the blade, when the air pressure in the cylinders isreieve In order to provide clean sections of the wipingtissue forcontact with the-blade faces each time the pushers 38 and 38' bring thewiping tissue into contact with the blade, the drawrolls 31 and 31' aredriven slowly intermittently and, with the assistance of the respectivesqueeze rolls 33 and 33, draw the strips of wiping tissue down from therespective supply rolls and over the ends of the pushers. For thepurpose of operating these draw rolls each draw roll is attached to aratchet wheel which is actuated by a pawl link connected with the pistonrod of the respective cylinder. The collars 39 and 39 (Fig. 2,) aresecured on the piston rods 35 and 35 respectively and in turn carry. thepawl links 41 and 41'. The ratchet wheel 40' for the draw, roll 31f isshown in Fig. 2, and it will be apparent from this figure that each timethe piston rod 35' moves from left to'right under the force of thespring 37' the ratchet wheel 40', and therewith the draw roll31', becaused to turn slightly in counter-clockwise direction. A similarratchet wheel (not shown) attached to the draw roll 30 and actuated bythe pawl link 41, moves the draw roll 30 correspondingly in clockwisedirection.

The operation of the wiper assembly will now be apparent. Whenever theair supply valve is opened and air under pressure causes the grinders tooperate, a supply of air will also be delivered to the cylinders 34 and34' moving the piston rods and pushers towards the rotating blade 10 andcausing the wiping tissue to be pressed against the faces of the blade.The pushers hold the tissue in contact with the blade for a short timeafter each grinding due to the control air valve which causes the air tobe exhausted slowly from the cylinders after the cylinders have beenactuated, thus holding the pushers and tissue against the blade longenough to clean the blade completely from any grinding residue.

Since the plate 14. is hingedly supported on the stationary shaft and isconnected with the blade shaft and moving support for the blade by therod 17, the plate 14 will oscillate slightly in a substantiallyhorizontal direction with the up and down arcuate movement oftherotating blade. Thisadditional relative movement of the wipingassemblyinsures the wiping of thefaces of the blade completely, not only at thecutting edge but also over the adjacent area on which there may be anygrinding particles or oil, and aids in providing the desired positivecleaning of the blade immediately after each grinding before the bladeenters upon its next cutting operation. Also the mounting ofthe plate 14and the entire wipingassembly on the stationary shaft 15 instead of on ashaft supported on the moving arm for the blade shaft causes only aminimum oscillating inertia load to be placed on the up and downmovement of the rotating cutting blade. When access to the rotatingblade isdesired the disconnecting of the rod 1'! enables the plate andentire. wiping assembly to belswung. up away from the blade.v Minor.modifications in the mechanism of the blade.wiping. .assemblyvwould.bepossible without 4 departing from the principle of the invention, butthat which is illustrated and described is considered'the preferredmeans for controlling the feeding of the wiping tissues and for bringingthem intermittently into wiping contact with the two faces of the blade.

I claim:

1. In a wiping assembly for a driven rotating cutter blade, a pair ofsupplyrolls of blade-wiping material,

supporting means for-said supply. rolls on opposite sides of said bladerespectively, guide means for guiding the blade-wipingmaterial from eachof said supply rolls in paths along oppositesides of said bladerespectively, means for moving the wiping material over said guidemeans, a pair of elementsengaging the wiping material on opposite sidesof said blade respectively and intermittently thrusting said materialinto contact with the respective faces of said blade, and means foroperating said elements.

2. In. a wipingassembly for a driven rotating cutter blade, a pair ofsupply rolls of blade-wiping material, supporting means for said supplyrolls on opposite sides of "said blade respectively, guide rollers onsaid supporting means for guiding the blade-wiping material from each ofsaid supply rolls in pvaths along opposite sides of saidbladerespectively, means on said supporting means for moving the wipingrnaterial over said rollers, a pair of pushers engaging the wipingmaterial on opposite sides. of said blade respectively andintermittently, thrusting saidmaterial intocontact with the respectivefaces of saidblade, andimeans on said supporting means for operatingsaidpushers.

3. In a wiping assembly'for a driven rotating cutter blade, a. mountingplate extending in a plane perpendicular tothe plane of said rotatingblade, means for supporting said plate, said plate having a slot, aportion of said blade extendingthrough said slot, a pair of-supply rollsof blade-wiping material mounted-on said plate on opposite sides of saidblade and said slot respectively,

operation of a one-way flow .ing plate extending in a guiderollersonsaid mounting plate for guiding the bladewiping material fromeach of said supply rolls in paths along opposite sides of said bladerespectively, means including a pair ofdraw rolls on said mounting plateon opposite sides of said blade respectively, for moving the wipingmaterial over said rollers, a pair of elements engaging the wipingmaterial onopposite sides of said blade respectively and intermittentlythrusting said material into contact with the respective faces ofsaid'blade, and means, on saidplate for operating saidelements and foroperating said draw rolls.

4. Ina wiping assembly for a driven rotating cutter blade of thecharacter described'mounted on a shaft and oscillating in a fixed plane,a mounting plate extending in a plane perpendicular to the plane, ofsaid rotating blade, said plate pivotally supported from a stationaryshaft extending parallel to the shaft of said blade, said plate having aslot, a portion of said blade extending through said slot, positioningmeans connecting the free end of said plate with said blade shaft, apair of supply rolls of blade-wiping material mounted on said plate onopposite sides of said blade respectively, guide means on said mountingplate for guiding the blade-wipingmaterial from each of said supplyrolls in paths along opposite sides of said blade respectively, meansfor moving the wiping material over said guide means, a pair of pushersengaging the wiping material on opposite sides of said bladerespectively and intermittently thrusting said material into contactwith the respective faces of said blade, and means forv operating saidpushers.

5 A Wiping assembly for a driven rotating cutter blade of the characterdescribed mountedon a shaft and oscillating in a fixed plane, saidassembly including-amount,-

plane perpendicular to the plane of said rotating blade, said platepivotallysupported from a; stationary shaft extending parallel tothe-shaftof said @s id; Plate. aving with statist cs Qiaa d. b ade 6extending through said slot, plate positioning means conmaterial onopposite sides of said blade respectively and necting the free end ofsaid plate with said blade shaft, intermittently thrusting said materialinto contact with a pair of supply rolls of blade-wiping materialmounted the respective faces of said blade, a pair of air cylinders onsaid plate on opposite sides of said blade respectively, and pistonssupported on said plate on opposite sides of guide rollers on saidmounting plate for guiding the 5 said blade respectively for operatingsaid pushers, and blade-wiping material from each of said supply rollsin means connected with said cylinder pistons for operating paths alongopposite sides of said blade respectively, said means for moving saidwiping material over said means on said mounting plate on opposite sidesof said guide rollers.

blade respectively for moving the wiping material over said guiderollers, a pair of pushers engaging the wiping 10 No references cited.

